National Fire Protection Association
National Electrical Code
Fact Sheet
Arc-Fault Circuit Interrupters
What are Arc-Fault Circuit Interrupters (AFCIs)?
The 2008 National Electrical Code (NEC) requirement for AFCI protection considerably expands this
fire prevention technology to the majority of circuits installed in new and renovated homes. The type of
AFCI currently available commercially is a next-generation circuit breaker that not only provides the
conventional safety functions, but its advanced design also rapidly detects potentially dangerous arcs and
disconnects power in the circuit before a fire can start. Fire safety officials throughout the U.S. endorse
AFCIs as a significant step forward in electrical fire safety.
Why should they be installed in homes?
AFCIs will save lives and make homes safer. According to the U.S. Fire Administration, each year home
electrical problems cause about 70,000 fires, resulting in 485 deaths and $868 million in property loss.
Why mandate AFCIs for newer homes when statistics show the majority of problems have occurred
in older homes?
Fire safety officials recommend the use of AFCIs in all dwellings. While it is true that fire statistics in
many cases are derived from older dwellings, damage to appliance cords or to wires hidden in a wall can
occur regardless of the home’s age. In addition, incorrectly performed electrical installations can occur in
both new and old homes. As technology evolves and the NEC is revised, the enhanced level of safety is
typically required only in new construction that is subject to the latest adopted edition. Homes wired per the
2008 NEC will have the majority of their circuits protect by AFCIs for the life of the electrical system.
How do you know AFCIs will prevent fires and save lives?
Since 1999, AFCIs have been thoroughly field-tested. Underwriters Laboratories, the National Association
of State Fire Marshals (NASFM), the U.S. Consumer Product Safety Commission, and many other experts
have found AFCIs to be reliable and effective. By eliminating a significant source of electrically related
fires, future statistics will demonstrate a reduction in fires of electrical origin.
Are AFCIs expensive?
The cost of the enhanced protection is directly related to the size of the dwelling and the number of circuits
installed. Current retail prices of AFCI-type circuit breakers at several national building supply chains are
in the range of $35 to $40 per unit. Even for larger homes with more circuits, the cost increase is
insignificant compared to the total cost of the home, particularly when the increased level of safety is
factored.
Do AFCIs interfere with smoke alarms and appliances, and trip unnecessarily?
AFCIs do not interfere with power supply reliability. These state-of-the-art devices identify problems that
current circuit breakers are not designed to protect against, which can result in what appears to be an
unexplained circuit breaker trip. By actually identifying these problems, residents are safer.
What is the NEC?
The NEC is the National Electrical Code. The NEC’s mission is to provide practical safeguards from the
hazards that arise from using electricity. It is the most widely adopted safety code in the United States and
the world, and it is the benchmark for safe electrical installations. The NEC is an evolving document,
developed through an open consensus process. A new edition is issued every three years.
For more information, visit www.nfpa.org.